ABSTRACT
Effect of vitamin E supplementation on growth performance, carcass characteristics and intramuscular fatty acid composition of Longissimus dorsi muscle in 'Tan' sheep

Tianzhang Zhao1,2, Hailing Luo1*, Yuwei Zhang1, Kong Liu1, Huina Jia1, Yanfei Chang1, Lijuan Jiao1, and Weimin Gao1
 
The beneficial effects on meat quality of adding vitamin E to diets have been extensively studied in cattle and lamb. However, how supplemental vit E affects the performance and meat quality of 'Tan' sheep has not been reported. Thirty-five male lambs of 'Tan' sheep (20-30 d after weaning) with similar body weight were randomly divided into five groups of seven each to receive a basal diet plus five levels of vit E supplementation: 0 (control group, CG), 20, 100, 200, and 2000 IU d-1 lamb-1. The results showed: 1) no differences were observed in animal growth performance between CG and vit E treated groups (VG) (P > 0.05); 2) vit E supplementation levels over 200 IU d-1 lamb1 dramatically suppressed subcutaneous fat deposition and similarly that above 100 IU d-1 lamb-1 considerably reduced drip loss and pH 24 h of Longissimus dorsi (LD) muscle in VG lambs compared to those of CG (P < 0.01), but with no significant effect on other carcass characteristics (P > 0.05); 3) although vit E supplementation generally did not affect the fatty acid composition of intramuscular lipids in LD muscle, the percentage of n-6 polyunsaturated fatty acids (PUFA) and the ratio of n-6/n-3 PUFA were significantly enhanced (P < 0.05) and an increasing tendency (P < 0.1) for both total PUFA proportion and the ratio of PUFA/saturated fatty acids (SFA) was also observed in 'Tan' sheep lambs treated with vit E. In conclusion, vit E supplementation of male 'Tan' sheep lambs did not influence growth performance, significantly reduced subcutaneous fat deposition, drip loss, pH 24 h and tended to improve fatty acid profile of LD muscle.
Keywords: Carcass characteristics, growth performance, vitamin E.
1China Agricultural University, College of Animal Science and Technology, Beijing, 100193, P.R. China. *Corresponding author (luohailing@cau.edu.cn).2Bio-Technology Department, Wulanchabu Vocational College, Wulanchabu, 012000, P. R. China.